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<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif;color:#1F497D">This option is-live instructs GST h264 decoder element to perform low latency mode for Live event, thus this option takes role of key configuration
of pipeline behavior in response to real-time decoding. In my opinion it should not be removed but more elaborate description is also needed to avoid misleading programmer.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.5pt;font-family:"Calibri",sans-serif;color:#1F497D">George<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"微软雅黑",sans-serif">发件人<span lang="EN-US">:</span></span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"微软雅黑",sans-serif"> gstreamer-devel [mailto:gstreamer-devel-bounces@lists.freedesktop.org]
</span><b><span style="font-size:11.0pt;font-family:"微软雅黑",sans-serif">代表 </span>
</b><span lang="EN-US" style="font-size:11.0pt;font-family:"微软雅黑",sans-serif">paolo perotinus<br>
</span><b><span style="font-size:11.0pt;font-family:"微软雅黑",sans-serif">发送时间<span lang="EN-US">:</span></span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"微软雅黑",sans-serif"> 2017</span><span style="font-size:11.0pt;font-family:"微软雅黑",sans-serif">年<span lang="EN-US">7</span>月<span lang="EN-US">11</span>日<span lang="EN-US">
18:50<br>
</span><b>收件人<span lang="EN-US">:</span></b><span lang="EN-US"> Discussion of the development of and with GStreamer <gstreamer-devel@lists.freedesktop.org><br>
</span><b>主题<span lang="EN-US">:</span></b><span lang="EN-US"> Re: </span>答复<span lang="EN-US">: How to reduce avdec_h264 latency<o:p></o:p></span></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:black">I just solved the problem (thanks to Tim-Philipp Muller) by setting is-live=1 on the receiver. The latency was added in
gstavviddec.c (check the line with: "gst_query_parse_latency (query, &is_live, NULL, NULL);" ).<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:black">However I think that this option (is-live) can appear too generic and misleading, and should be removed/changed.<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:black">What do you think about?<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt;background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial",sans-serif;color:black">Il Martedì 11 Luglio 2017 12:40, "Lijia (George Lee, Euler)" <<a href="mailto:george.lee@huawei.com">george.lee@huawei.com</a>>
ha scritto:</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt;background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black">Pls take a bit of time to delve into system –level thread scheduling in attempt to find clue to long latency in plugin implementation.
As per experience excluding bitstream encoding option, in many situations we often can find negative impact brought by threading scheduling over Linux. Even though bitstream has been encoded very well for low-latency use-case such as removal of B-frame/sub-frame
processing (parallel pipeline), implicit threading scheduling defect is hard to find.
</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black"> </span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black">Best Regards,</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black"> </span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black">George Lee
</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.5pt;font-family:"Helvetica",sans-serif;color:black"> </span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><b><span style="font-size:11.0pt;color:black">发件人</span></b><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
gstreamer-devel [<a href="mailto:gstreamer-devel-bounces@lists.freedesktop.org">mailto:gstreamer-devel-bounces@lists.freedesktop.org</a>]
</span><b><span style="font-size:11.0pt;color:black">代表</span></b><b><span style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">paolo perotinus<br>
</span><b><span style="font-size:11.0pt;color:black">发送时间</span></b><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
2017</span><span style="font-size:11.0pt;color:black">年</span><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">7</span><span style="font-size:11.0pt;color:black">月</span><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">11</span><span style="font-size:11.0pt;color:black">日</span><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
17:45<br>
</span><b><span style="font-size:11.0pt;color:black">收件人</span></b><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
Discussion of the development of and with GStreamer <<a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a>><br>
</span><b><span style="font-size:11.0pt;color:black">主题</span></b><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Helvetica",sans-serif;color:black">
Re: How to reduce avdec_h264 latency</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:black">Il Martedì 11 Luglio 2017 1:06, Olivier Crête <<a href="mailto:olivier.crete@collabora.com" target="_blank">olivier.crete@collabora.com</a>>
ha scritto:</span><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"><o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black">> Hi,
<br>
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> The only way to do that is to create a stream with no B-frames, for example using the H. 264 baseline profile.
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> Olivier <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black">Hi Olivier,<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black">The stream is already coded with no B-frames (zerolatency tune in ffmpeg) but I still have that latency in avdec_h264...<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span lang="EN-US" style="font-family:"Helvetica",sans-serif;color:black">_______________________________________________<br>
gstreamer-devel mailing list<br>
<a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a><br>
<a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><o:p></o:p></span></p>
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